Which modality is associated with metal fragments or artifacts risk?

Which modality is associated with metal fragments or artifacts risk?

• A. Ultrasound
• B. MRI
• C. Nuclear Medicine (PET Scan)
• D. X-ray

Answer: (B)

MRI involves a strong magnetic field, which creates metal-related safety and artifact concerns. Ferromagnetic fragments can be attracted to the magnet or heat up, posing a risk to the patient. Even nonferromagnetic metals disturb the local magnetic field, causing susceptibility artifacts that appear as signal loss and geometric distortion around the fragment, which can obscure anatomy and complicate interpretation. That combination—safety risk plus image distortion around metal—is why MRI is the modality most associated with metal fragments or artifacts. Ultrasound is generally safe with metal fragments, though metal can cause acoustic shadowing. X-ray and CT visualize metal well and are not driven by magnetism, though metal can produce streak artifacts in CT. Nuclear medicine imaging is not affected by the magnetic field, so metal does not introduce the same artifact risk in that modality.

MRI involves a strong magnetic field, which creates metal-related safety and artifact concerns. Ferromagnetic fragments can be attracted to the magnet or heat up, posing a risk to the patient. Even nonferromagnetic metals disturb the local magnetic field, causing susceptibility artifacts that appear as signal loss and geometric distortion around the fragment, which can obscure anatomy and complicate interpretation. That combination—safety risk plus image distortion around metal—is why MRI is the modality most associated with metal fragments or artifacts.

Ultrasound is generally safe with metal fragments, though metal can cause acoustic shadowing. X-ray and CT visualize metal well and are not driven by magnetism, though metal can produce streak artifacts in CT. Nuclear medicine imaging is not affected by the magnetic field, so metal does not introduce the same artifact risk in that modality.